Fix/issue 14 b tree (#15)

Author: tzaeschke

CHANGELOG.md

@@ -6,6 +6,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## [Unreleased]
 ### Changed
+- DIM>8 now uses custom b_plus_tree_map instead of std::map. This improves performance for all operations, e.g.
+  window queries on large datasets are up to 4x faster. Benchmarks results can be found in the issue. 
+  [#14](https://github.com/tzaeschke/phtree-cpp/issues/14)
 - postfix/infix field moved from Node to Entry. This avoids indirections and improves performance of most by ~10%.
   operations by 5-15%.  [#11](https://github.com/tzaeschke/phtree-cpp/issues/11)
 - Entries now use 'union' to store children.  [#9](https://github.com/tzaeschke/phtree-cpp/issues/9)

LICENSE

@@ -188,6 +188,7 @@
       identification within third-party archives.
 
    Copyright 2020 Improbable Worlds Limited
+   Copyright 2022 Tilmann Zäschke
 
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.

TODO.txt

@@ -0,0 +1,76 @@
+Fix const-ness
+==============
+- operator[] should have a const overload
+- find() should have a non-const overload
+- test:
+
+TEST(PhTreeTest, SmokeTestConstTree) {
+    // Test edge case: only one entry in tree
+    PhPoint<3> p{1, 2, 3};
+    TestTree<3, Id> tree1;
+    tree1.emplace(p, Id{1});
+    tree1.emplace(p, Id{2});
+    Id id3{3};
+    tree1.insert(p, id3);
+    Id id4{4};
+    tree1.insert(p, id4);
+    const auto& tree = tree1;
+    ASSERT_EQ(tree.size(), 1);
+    ASSERT_EQ(tree.find(p).second()._i, 1);
+    ASSERT_EQ(tree[p]._i, 1);
+
+    auto q_window = tree.begin_query({p, p});
+    ASSERT_EQ(1, q_window->_i);
+    ++q_window;
+    ASSERT_EQ(q_window, tree.end());
+
+    auto q_extent = tree.begin();
+    ASSERT_EQ(1, q_extent->_i);
+    ++q_extent;
+    ASSERT_EQ(q_extent, tree.end());
+
+    auto q_knn = tree.begin_knn_query(10, p, DistanceEuclidean<3>());
+    ASSERT_EQ(1, q_knn->_i);
+    ++q_knn;
+    ASSERT_EQ(q_knn, tree.end());
+
+    ASSERT_EQ(1, tree1.erase(p));
+    ASSERT_EQ(0, tree.size());
+    ASSERT_EQ(0, tree1.erase(p));
+    ASSERT_EQ(0, tree.size());
+    ASSERT_TRUE(tree.empty());
+}
+
+
+b_plus_tree_map - binary search
+===============
+Use custom binary search:
+
+    // return BptEntry* ?!?!?
+    template <typename E>
+    [[nodiscard]] auto lower_bound(key_t key, std::vector<E>& data) noexcept {
+        return std::lower_bound(data.begin(), data.end(), key, [](E& left, const key_t key) {
+            return left.first < key;
+        });
+        //        auto pos = __lower_bound(&*data_leaf_.begin(), &*data_leaf_.end(), key);
+        //        return data_leaf_.begin() + pos;
+    }
+
+    template <typename TT>
+    inline auto __lower_bound(const TT* __first, const TT* __last, key_t __val) const noexcept {
+        const TT* const_first = __first;
+        auto __len = __last - __first;
+
+        while (__len > 0) {
+            auto __half = __len >> 1;
+            const TT* __middle = __first + __half;
+            if (__middle->first < __val) {
+                __first = __middle;
+                ++__first;
+                __len = __len - __half - 1;
+            } else
+                __len = __half;
+        }
+        return __first - const_first;
+    }
+

WORKSPACE

@@ -34,9 +34,9 @@ http_archive(
 
 http_archive(
     name = "gbenchmark",
-    sha256 = "dccbdab796baa1043f04982147e67bb6e118fe610da2c65f88912d73987e700c",
-    strip_prefix = "benchmark-1.5.2",
-    url = "https://github.com/google/benchmark/archive/v1.5.2.tar.gz",
+    sha256 = "6132883bc8c9b0df5375b16ab520fac1a85dc9e4cf5be59480448ece74b278d4",
+    strip_prefix = "benchmark-1.6.1",
+    url = "https://github.com/google/benchmark/archive/v1.6.1.tar.gz",
 )
 
 http_archive(

phtree/benchmark/BUILD

@@ -304,3 +304,63 @@ cc_binary(
         "@spdlog",
     ],
 )
+
+cc_binary(
+    name = "hd_insert_d_benchmark",
+    testonly = True,
+    srcs = [
+        "hd_insert_d_benchmark.cc",
+    ],
+    linkstatic = True,
+    deps = [
+        "//phtree",
+        "//phtree/benchmark",
+        "@gbenchmark//:benchmark",
+        "@spdlog",
+    ],
+)
+
+cc_binary(
+    name = "hd_erase_d_benchmark",
+    testonly = True,
+    srcs = [
+        "hd_erase_d_benchmark.cc",
+    ],
+    linkstatic = True,
+    deps = [
+        "//phtree",
+        "//phtree/benchmark",
+        "@gbenchmark//:benchmark",
+        "@spdlog",
+    ],
+)
+
+cc_binary(
+    name = "hd_query_d_benchmark",
+    testonly = True,
+    srcs = [
+        "hd_query_d_benchmark.cc",
+    ],
+    linkstatic = True,
+    deps = [
+        "//phtree",
+        "//phtree/benchmark",
+        "@gbenchmark//:benchmark",
+        "@spdlog",
+    ],
+)
+
+cc_binary(
+    name = "hd_knn_d_benchmark",
+    testonly = True,
+    srcs = [
+        "hd_knn_d_benchmark.cc",
+    ],
+    linkstatic = True,
+    deps = [
+        "//phtree",
+        "//phtree/benchmark",
+        "@gbenchmark//:benchmark",
+        "@spdlog",
+    ],
+)

phtree/benchmark/benchmark_util.h

@@ -91,7 +91,7 @@ auto CreateDuplicates =
     };
 }  // namespace
 
-enum TestGenerator { CUBE, CLUSTER };
+enum TestGenerator { CUBE = 4, CLUSTER = 7 };
 
 template <dimension_t DIM>
 auto CreatePointDataMinMax = [](auto& points,

phtree/benchmark/hd_erase_d_benchmark.cc

@@ -0,0 +1,145 @@
+/*
+ * Copyright 2020 Improbable Worlds Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include "logging.h"
+#include "phtree/benchmark/benchmark_util.h"
+#include "phtree/phtree.h"
+#include <benchmark/benchmark.h>
+#include <random>
+
+using namespace improbable;
+using namespace improbable::phtree;
+using namespace improbable::phtree::phbenchmark;
+
+namespace {
+
+const int GLOBAL_MAX = 10000;
+
+/*
+ * Benchmark for removing entries.
+ */
+template <dimension_t DIM>
+class IndexBenchmark {
+  public:
+    IndexBenchmark(benchmark::State& state);
+    void Benchmark(benchmark::State& state);
+
+  private:
+    void SetupWorld(benchmark::State& state);
+    void Insert(benchmark::State& state, PhTreeD<DIM, int>& tree);
+    void Remove(benchmark::State& state, PhTreeD<DIM, int>& tree);
+
+    const TestGenerator data_type_;
+    const int num_entities_;
+
+    std::default_random_engine random_engine_;
+    std::uniform_real_distribution<> cube_distribution_;
+    std::vector<PhPointD<DIM>> points_;
+};
+
+template <dimension_t DIM>
+IndexBenchmark<DIM>::IndexBenchmark(benchmark::State& state)
+: data_type_{static_cast<TestGenerator>(state.range(1))}
+, num_entities_(state.range(0))
+, random_engine_{1}
+, cube_distribution_{0, GLOBAL_MAX}
+, points_(state.range(0)) {
+    logging::SetupDefaultLogging();
+    SetupWorld(state);
+}
+
+template <dimension_t DIM>
+void IndexBenchmark<DIM>::Benchmark(benchmark::State& state) {
+    for (auto _ : state) {
+        state.PauseTiming();
+        auto* tree = new PhTreeD<DIM, int>();
+        Insert(state, *tree);
+        state.ResumeTiming();
+
+        Remove(state, *tree);
+
+        state.PauseTiming();
+        // avoid measuring deallocation
+        delete tree;
+        state.ResumeTiming();
+    }
+}
+
+template <dimension_t DIM>
+void IndexBenchmark<DIM>::SetupWorld(benchmark::State& state) {
+    logging::info("Setting up world with {} entities and {} dimensions.", num_entities_, DIM);
+    CreatePointData<DIM>(points_, data_type_, num_entities_, 0, GLOBAL_MAX);
+
+    state.counters["total_remove_count"] = benchmark::Counter(0);
+    state.counters["remove_rate"] = benchmark::Counter(0, benchmark::Counter::kIsRate);
+
+    logging::info("World setup complete.");
+}
+
+template <dimension_t DIM>
+void IndexBenchmark<DIM>::Insert(benchmark::State&, PhTreeD<DIM, int>& tree) {
+    for (int i = 0; i < num_entities_; ++i) {
+        tree.emplace(points_[i], i);
+    }
+}
+
+template <dimension_t DIM>
+void IndexBenchmark<DIM>::Remove(benchmark::State& state, PhTreeD<DIM, int>& tree) {
+    int n = 0;
+    for (int i = 0; i < num_entities_; ++i) {
+        n += tree.erase(points_[i]);
+    }
+
+    state.counters["total_remove_count"] += n;
+    state.counters["remove_rate"] += n;
+}
+
+}  // namespace
+
+template <typename... Arguments>
+void PhTree6D(benchmark::State& state, Arguments&&...) {
+    IndexBenchmark<6> benchmark{state};
+    benchmark.Benchmark(state);
+}
+
+template <typename... Arguments>
+void PhTree10D(benchmark::State& state, Arguments&&...) {
+    IndexBenchmark<10> benchmark{state};
+    benchmark.Benchmark(state);
+}
+
+template <typename... Arguments>
+void PhTree20D(benchmark::State& state, Arguments&&...) {
+    IndexBenchmark<20> benchmark{state};
+    benchmark.Benchmark(state);
+}
+
+// index type, scenario name, data_generator, num_entities
+BENCHMARK_CAPTURE(PhTree6D, ERASE, 0)
+    ->RangeMultiplier(10)
+    ->Ranges({{1000, 1000 * 1000}, {TestGenerator::CLUSTER, TestGenerator::CUBE}})
+    ->Unit(benchmark::kMillisecond);
+
+BENCHMARK_CAPTURE(PhTree10D, ERASE, 0)
+    ->RangeMultiplier(10)
+    ->Ranges({{1000, 1000 * 1000}, {TestGenerator::CLUSTER, TestGenerator::CUBE}})
+    ->Unit(benchmark::kMillisecond);
+
+BENCHMARK_CAPTURE(PhTree20D, ERASE, 0)
+    ->RangeMultiplier(10)
+    ->Ranges({{1000, 1000 * 1000}, {TestGenerator::CLUSTER, TestGenerator::CUBE}})
+    ->Unit(benchmark::kMillisecond);
+
+BENCHMARK_MAIN();